Method Of Screening Drugs For Reversal Of Amyloid Beta Neurotoxicity

Abstract

A method of screening a compound for effectiveness in treating amyloid beta neurotoxicity comprises culturing mammalian neurons in serum-free defined medium until the neurons are electrically functional, exposing the electrically stable neurons to amyloid beta, monitoring the exposed neurons for impairment of electrical functionality, and treating the exposed neurons with the candidate drug while monitoring their electrical activity for reversal of impairment. The invention also includes a method of identifying a mammalian neuron having a biological marker conferring predisposition to development of Alzheimer's disease, the method comprising culturing the mammalian neuron in serum-free medium until the neuron is electrically functional, exposing the electrically stable neuron to amyloid beta while monitoring for impairment of electrical functionality as an indicator of presence of said biological marker, and verifying presence of the biological marker by treating the impaired neuron with an anti-amyloidogenic compound while monitoring for return of neuron functionality.

Description

RELATED APPLICATION[0001]This application claims priority from co-pending provisional application Ser. No. 61 / 181,718, which was filed on 28 May 2009, and which is incorporated herein by reference in its entirety.STATEMENT OF GOVERNMENT RIGHTS[0002]The invention claimed herein was made with at least partial support from the U.S. Government. Accordingly, the government may have certain rights in the invention, as specified by law.FIELD OF THE INVENTION[0003]The present invention relates to the field of neurodegenerative diseases and, more particularly, to an in vitro system for screening drugs effective for treatment of nerve cells expressing electrical impairment caused by amyloid beta.BACKGROUND OF THE INVENTION[0004]We have demonstrated that high-throughput electrophysiology techniques can be used to measure Amyloid beta (Aβ) toxicity in neurons and that the effects of this toxicity can be reversed by a drug application. In addition, we believe we have identified a new target for ...

AI Technical Summary

Benefits of technology

[0010]Patch clamp studies detailed here have demonstrated that soluble Aβ can also cause functional toxicity, namely it inhibits spontaneous firing of hippocampal neurons without significant cell death at low concentrations. This toxicity will eventually lead to the loss of the synapse as well, but may precede this loss by a considerable amount of time. In a key technological advance we have reproduced these results utilizing a fast and simple method based on extracellular electrophysiological recording of the temporal electrical activity of cultured hippocampal neurons using multielectrode arrays (MEAs) at low concentrations of Aβ (1-42). We have also shown that this functional deficit can be reversed through use of curcumin, an inhibitor of Aβ oligomerization, using both analysis methods.

[0011]The MEA recording method utilized here is non-invasive, thus long term chronic measurements are possible and it does not require precise positioning of electrodes, thus it is ideal for functional screens. Even more significantly, we believe we have now identified a new target for drug development for AD based on functional toxicity of hippocampal neurons that could treat neurodegenerative diseases prior to the development of mild cognitive impairment.

[0012]With the foregoing in mind, the present invention advantageously provides a high-throughput in vitro method for the assessment of Aβ effects on spontaneous activity of cultured neurons which can be adapted for high-throughput pharmaceutical screening. This assertion is supported by the emerging view that functional impairment of neurons might be more important for the development of AD symptoms than the actual cell death which occurs at later stages of the disease [1,2]. The results obtained with MEAs correlate well with those obtained using patch clamp electrophysiology wherein Aβ at low concentrations had a deleterious effect on cell functionality without significant cell death. We have also shown that this effect can be reversed to varying degrees using an anti-amyloidogenic compound. The MEA recording method utilized here is non-invasive, thus long term chronic measurements are possible and it does not require precise positioning of electrodes, thus it is ideal for functional screens. Even more significantly, we believe we have now identified a new target for drug development for AD based on functional toxicity of hippocampal neurons.

Problems solved by technology

Patch clamp studies detailed here have demonstrated that soluble Aβ can also cause functional toxicity, namely it inhibits spontaneous firing of hippocampal neurons without significant cell death at low concentrations.

This toxicity will eventually lead to the loss of the synapse as well, but may precede this loss by a considerable amount of time.

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